Pathogenic microorganisms are microorganisms that cause diseases in humans and animals, and easily produce infections or even infectious diseases. During operations such as tests and experiments on pathogenic microorganisms, hazardous biological aerosols are formed easily. If the hazardous biological aerosols scatter outside a laboratory, the environment in and around the laboratory will be severely polluted and a major public health event will be caused. Therefore, to ensure personal safety, contaminated air discharged by a biosafety facility such as a laboratory needs to be filtered.
Currently, a high efficiency particulate air (HEPA) filter is usually used to filter contaminated air discharged by a biosafety facility such as a laboratory. The HEPA filter serves as one of the most important secondary barriers, and is a main technical measure to prevent hazardous particles in the air inside the biosafety facility such as a laboratory from entering the outdoor environment.
Currently, the bacterial filtration efficiency of a HEPA filter is close to 100%. However, pathogenic microorganisms captured by the HEPA filter are very likely to survive and multiply under suitable temperature and humidity conditions. That is, there is a risk that pathogenic microorganisms may survive and multiply on the surface of the HEPA filter. Currently, a decontamination method using gaseous or vaporous fumigation is mainly used to perform further gas decontamination on the HEPA filter, so as to eliminate pathogenic microorganisms that exist on the surface of the HEPA filter.
However, an actual decontamination effect of the existing decontamination method using gas fumigation depends on various factors such as the type of a disinfectant, the dosage of a disinfectant, a decontamination volume, the temperature of a decontamination object, the humidity of a decontamination object, the decontamination effect time, and the permeation of a disinfectant in a filtering material. As a result, the decontamination effect of the decontamination method is relatively unpredictable, which easily causes great potential safety hazards to the replacement of a HEPA filter and other tests and maintenance.
For this, the validation of a decontamination effect becomes a critical step to ensure that a requirement of in situ gas decontamination is met. Currently, some international standards set out clear requirements. For example, Biosafety in Microbiological and Biomedical Laboratories (5th) from the United States Centers for Disease Control and Prevention (CDC) requires that the HEPA filter housings should be designed to allow for in situ decontamination and validation of the filter prior to removal.
Therefore, currently, there is an urgent need to develop a device that can reliably validate a decontamination effect of a HEPA filter in time, thereby effectively preventing pathogenic microorganisms that exist on the surface of the HEPA filter from spreading outside a biosafety facility such as a laboratory, avoiding polluting the external environment of the biosafety facility such as a laboratory, and ensuring personal safety.